Perceptual learning in humans: Roles of preexposure schedule, feedback, and discrimination assay

In three experiments, humans received preexposure to two compound flavours (AX and BX: saline-lemon and sucrose-lemon) that were presented either in an intermixed (e.g., AX, BX, . . . BX, AX, . . .) or a blocked (e.g., AX, AX, . . . BX, BX. . .) fashion. Subsequently, AXwas paired with an unpleasant bitter taste, and the discriminability of AX and BX was assessed using the accuracy of same/different judgements and by the extent to which any learned dislike of AX generalized to BX. When participants received feedback about the accuracy of their same/different judgements during preexposure those given intermixed preexposure were more accurate in making these judgements during the test than those given blocked preexposure (Experiments 1 and 2A), however, there was no evidence of any learned dislike in these experiments. In Experiment 2B, in which participants did not receive feedback about the accuracy of their judgements, there was no effect of the preexposure regime on same/different judgements, but there was a learned dislike of AX, and this generalized less to BX in participants given intermixed than in those given blocked preexposure. The beneficial effects of intermixed preexposure are consistent with results from other species (chicks and rats), but the differences created by the presence or absence of feedback place constraints on the analysis of these effects.     

Behavioral Risk Assessment of the Guarded Suicidal Patient

Psychiatrists and other mental health professionals are trained to assess patients by direct observation and examination. Short inpatient length of stay, brief outpatient visits, emergency room evaluations, and other time‐limited clinical settings require rapid assessment of suicide risk. Recognition of behavioral suicide risk factors can assist in the early identification of the guarded suicidal patient, thus avoiding total reliance on the patient's reporting.     

Reliability and sensitivity of suicide certification in higher-income countries.

World Health Organization age-, sex-, and cause-specific mortality data for the United States and 19 other democratic higher-income countries were utilized to assess the reliability and sensitivity of suicide certification for purposes of cross-national research. Data are found to be highly reliable across age and sex (rs > 0.92; P < 0.001). Relative discrepancies between official suicide rates (putative lower limits) and projected upper limits vary widely internationally. Austrian and Dutch suicide certification is the most sensitive. Least sensitive is certification for certain subpopulations in Finland, Greece, Ireland, Israel, and the United Kingdom. We recommend similar analyses be performed for routine, low-cost surveillance of suicide data quality, and to guide choice of population groups for multivariate comparative research.     

Reciprocal influences in children's and families' adaptation to early childhood wheezing.

OBJECTIVE: The objective of the present study was to demonstrate the reciprocal relationships between family adaptation to illness and children's medication use over time among children who presented with wheezing illness in infancy but have varying illness outcomes by age 4. DESIGN: A longitudinal design and latent growth curve models (LGM) were used to predict change in family and caregiver adaptation to illness and children's medication use over three years among 140 infants with wheezing, among families from low socioeconomic, multi-ethnic backgrounds. MAIN OUTCOME MEASURES: One LGM predicted level and change (slope) of family adaptation to illness from children's baseline medication use. The second LGM predicted level and change (slope) of children's medication use from baseline family adjustment to illness. In both models, illness severity, caregivers' psychological resources, and emergency department use were covaried with the independent variable. RESULTS: Two latent growth models were found to adequately fit the data and demonstrate full reciprocal relations between family adaptation to illness and children's medication use while accounting for baseline variables. Baseline measures of caregiver psychological functioning and illness severity were also significant predictors of family adaptation and children's medication use over time. The two models were not statistically different for children with and without active asthma at 4 years of age. CONCLUSION: Findings support the reciprocal effects model of child and family influences on pediatric illness and underscore the importance of early indicators of individual and family functioning.     

Parity still isn't a generalisation problem

Clark & Thornton take issue with my claim that parity is not a generalisation problem, and that nothing can be inferred about back-propagation in particular, or learning in general, from failures of parity generalisation. They advance arguments to support their contention that generalisation is a relevant issue. In this continuing commentary, I examine generalisation more closely in order to refute these arguments. Different learning algorithms will have different patterns of failure: back-propagation has no special status in this respect. This is not to deny that a particular algorithm might fortuitously happen to produce the "intended" function in an (oxymoronic) parity-generalisation task.     

Deconstructing Locus of Control: Implications for Practitioners

Locus of control is demonstrated as being an important individual belief for counselors to consider in their work. Western cultural bias that has influenced the research with locus of control, and may influence how counselors conceptualize clients' problems, is the notion that internal control is always more desirable than external control. Several areas of locus of control theory are reviewed, including sociocultural influences in the formation of the theory, cultural differences in locus of control, and differing conceptualizations of the construct. In addition, selected research with locus of control and mental health is briefly reviewed. Finally, important implications for practitioners are suggested.